From secunia security advisory at $URL; Description: The vulnerability is caused due to an error within the "apparmor_setprocattr()" function (security/apparmor/lsm.c), which can be exploited to trigger a "BUG_ON()" if a process writes malformed data to its "/attr/current" proc file. Solution: Fixed in the GIT repository. http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commitdiff;h=a5b2c5b2ad5853591a6cac6134cd0f599a720865
CVE-2011-3619 (http://nvd.nist.gov/nvd.cfm?cvename=CVE-2011-3619): The apparmor_setprocattr function in security/apparmor/lsm.c in the Linux kernel before 3.0 does not properly handle invalid parameters, which allows local users to cause a denial of service (NULL pointer dereference and OOPS) or possibly have unspecified other impact by writing to a /proc/#####/attr/current file.
There are no longer any 2.x kernels available in the repository with the exception of sys-kernel/xbox-sources which is unsupported by security.